In a medium bowl, combine 2 cups all purpose flour, ½ teaspoon baking powder, ½ teaspoon baking soda, ½ teaspoon salt. Set aside.
In a large bowl, using a hand mixer beat 1 cup softened unsalted butter with 1 cup granulated sugar and ½ cup powdered sugar until smooth and creamy.
Add in 1 large egg and 1 teaspoon vanilla extract and mix again.
Pour the dry ingredients into the wet ingredients. Use the hand mixer to combine, but do not overmix.
Gently fold in ½ cup rainbow sprinkles using a spatula. Do not overmix as the sprinkles can bleed color easily.
Drop 2 tablespoon cookie batter on to a large baking sheet, with each cooking 2" apart. Bake for 9-11 minutes. Remove from oven and let sit 10 minutes before using a thin spatula to transfer cookies to rack to cool completely.